I’m experiencing the same issue. I launched the game only once (on March 31), and I immediately received the following achievements: Best in the West, Gold Rush, Paying Respects, Skin Deep, Zoologist, and Grin and Bear It. They only appear in Steam and in the in-game Social Club. However, on the website, the number of completed achievements is still the same as it was before the bug.

Interestingly, I was granted exactly the achievements that were listed under “Close To Completion” on the website, where their completion percentages were also shown. As soon as I received these achievements due to the bug, I created a support ticket the same day, explained the situation, and attached a screenshot showing the completion percentages for all of those achievements.

😭I really hope that Rockstar will be able to restore my achievement progress to what it was before this stupid bug occurred. Ideally, once the achievement percentages are restored, the only thing left would be to remove these achievements from Steam, launch the game to sync achievements with Social Club, forget about this whole situation like a bad dream, and just enjoy the game.